Patent US4688629A successfully refreshed from Google Patents.
US4688629A
Expired / Lapsed
US
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Heat recuperator having ceramic core
Assignee: Osram Sylvania Inc
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Filing: 1981-11-23
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Granted: 1987-08-25
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Expires: 2001-11-23
Abstract
Abstract In a recuperator having a ceramic core within a housing, a layer of intumescent material is disposed between a solid face of the core and the housing to aid in securing the core within the housing.
Inventors
- 👤 Kent H. Kohnken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:18
CPC Classifications
F; F28; F28F; F28F21/00; F28F21/04; Y; Y10; Y10S; Y10S165/00; Y10S165/051; Y10S165/071; Y10S165/905
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
44 words
In a recuperator comprising a ceramic heat-exchanger core within a housing, the core having six faces, two solid and four having openings for the flow of gas therethrough, the improvement comprising a layer of intumescent material disposed between a solid face and the housing.
Claim 2
Dependent Claim
44 words
In a recuperator comprising a ceramic heat-exchanger core within a housing, the core having six faces, two solid and four having openings for the flow of gas therethrough, the improvement comprising a layer of intumescent material disposed between a solid face and the housing.
Claim 3
Dependent Claim
20 words
The recuperator of claim 1 wherein there is a layer of intumescent material between each solid face and the housing.
Claim 4
Dependent Claim
19 words
The recuperator of claim 1 wherein the layer of intumescent material maintains the core under compression within the housing.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |